Manufacture of concrete piles



Aug. 31 1926.

E. F. CYKLER MANUFACTURE OF CONCRETE FILES Filed Jan. 29 1923 1/2 Dell/0i Patented Aug. 31,

UbllTED STATES EIVIIL F. CYKLER, OF LOS ANGEL-ES, CALIFORNIA.

MANUFACTURE OF CGNCBETE PZLES.

Application filed January 29, 1923.

This invention relates to the formation of hollow concrete bodies, such for instance, as hollow concrete piles wherein it is desired to have a central longitudinal opening for any purpose, as for the escape of steam from the inner parts of the concrete in a process for saturating the concrete with a hot water proofing compound; and the general object of the invention is the provision of a method and apparatus for manufacturing such piles with an internal longitudinal opening. Other objects and features of the invention will be explained hereinafter and will be best understood from the following detailed description.

I have found from my experience that it is diiiicult to construct long concrete piles and to form longitudinal hole with a roandrel or core, on account of the n'iandrel or core adhering to the concrete and causing disintegration of the inner wall when it is adapted to remove the mandrel or core. I have found that if the cores are tapered slightly and particularly if they are rotated intermittently during the setting of the concrete, they may be comparatively easily withdrawn; and my apparatus provides not only these features but also provides a means whereby the cores may be started easily. Once the cores are started they may then be withdrawn without any trouble.

All of this will be best understood from the following detailed specification wherein I explain the particulars of preferred forms of apparatus, reference for this purpose being had to the accompanying drawings in which Fig. 1 is a longitudinal central section showing a concrete pile and showing my cores in place;

Fig. 2 is fragmentary sectional enlargement of'certain parts shown in Fig. 1;

Fig. 3 is a section on line 33 of Fig. 2;

Fig. t is a sectional view showing a modification hereinafter described; and

Fig. 5 is a section on line 55 of Fig. t.

In the drawings I show a concrete mass at within a form or mold 11, this mold having ends 12 with central apertures through which the cores may be inserted. These cores are preferably at least in two parts. each tapering toward its inner end and there are connected by the screw-thread ed joint indicated generally by the numeral 13. For convenience in making up these cores, which are usually comparatively long Serf-a1 No. 615,567.

and made of pipe machined to an exterior taper, it will also usually be made in two or more sections. For instance, in the drawings I show each tapered half core to be constructed of two sections A, B and A B and these sections are connected together by the screw threaded joint indicated generally by the numeral l l. Screw threaded joint 13 may conveniently be formed by welding a hollow plug 15 into one of the sections, say B this plug having a screw threaded pin 16 that screws into the internal threads indicated at 13 in section B. Likewise the screw threaded connections between the two sections of each half core maybe formed by welding or otherwise securing a plug 15 in one of the sections, this plug having screw threaded connection similar to that described. These plugs are preferably hollow, provided with bores 17 to permit passage of air to relieve the vacuum that would otherwise be formed between the two core halves when those two halves are pulled. or forced apart to remove them from the concrete.

Each end of the core is provided with apertures 18 for the insertion of a pin for turning the whole core from time to time during the setting of the concrete to prevent adherence of the concrete to the core, the exterior surface of the core being machined smoothly to facilitate this operation and to facilitate withdrawal of the core. When the concrete has set sufficiently, then the cores are started outwardly by turning them, relatively, in opposite directions to unscrew the joint at 13; and by this unscrewing action the two core halves are forced apart and the core thus started out of the mold. By the construction which has been described air has free access throughout the length of the whole core; and bythe construction of the threads at joint 13 in such a manner as to make these threads not fluid tight, air is admitted, through the threads, to the shouldered abutment at 20 between the two core halves. hen these shouldered abutments are forced apart, the air entering the space between them relieves the vacuum that would otherwise be formed and thus prevents disintegration or collapse of the inner concrete wall at that point. If this vacuum is not relieved I have found that the concrete wall at that point will collapse when the cores are forced apart; particularly because it is desirable to withdraw the cores while the concrete is still greenat a time when r. all

the concrete has just set sufficient to acquire strength enough to stand up of itself. It is readily understood in the art how the threads 1.3 may be formed to make a mechanically tight connection, or to bring the shoulders at into firm abutment with each other, and still at the same time have the threads not fluid tight. For instance, this may be done by making the external and internal threads at 13 of the same pitch but by making one deeper than the other. The same function may be performed, even with a fluid tight thread at 13, by providing a small hole or holes at 21, as shown in Fig. 2, leading from the bore 17 to the shoulder at 20.

To provide that the threads at 14 shall not be unset during either the screwing up or unscrewing of the joint at 13, these threads at 14 may be fitted more tightly than those at 13, or the joint at 1A may be permanently set as for instance by a key-pin, such as illustrated at 22. It is understood of course that the joints at l l are only provided to facilitate the original manufacture of the cores and that they are not, during the operations here described, taken apart.

As a modified form of arrangement for admitting air to the shoulders at 20, I may use a plug such as shown at 15 in Figs. 4 and 5, this plug being providedin its surface with a longitudinal groove that leads to the shoulders at 20.

Thecores may be made of any suitable material and preferably should each be ap proximately half the lengthof the pile in which they are used. The cores may be suitably supported in the form in any manner; I show them here as supported by the ends 12, but they can also be supported in other manners well known in the art. After the cores have been started by unscrewing the joint at 13, they can then be easily removed longitudinally at each end; all with out any danger of breaking down the concrete surface. I thus overcome all the chiliculties encountered heretofore. v

lVhile I have described a p eferred and specific form of apparatus in full detail, I have done so in order that those skilled in the art may fully understand the invention by having a full and detailed understanding of one form thereof; and accordingly I do not limit the invention to the particular and specific things herein described, except as specifically so limited in the following claims.

Having described a preferred form of my invention, I claim 1. A method of forming an internal opening in a concrete body with the use of two core halves entering from opposite ends of the body and abutting at their inner ends, that includes forming the concrete about the cores, allowing the concrete to partially set, rotating the cores intermittently during the setting of the concrete to prevent adhesion of the concrete to the core surface, then Withdrawing the-cores longitudinally in the opposite directions, and admitting air to the space between the abutting c-ore ends as the cores are withdrawn.

2. A core comprising two tapered members of circular cross-section adapted to abut at their smaller ends, a screw threaded joint between the members at their smaller ends, and means to allow access of atmosphere to the core abutments, for the purposes described. 1

3. A core comprising two tapered members of circular cross section adapted to abut at their smaller ends, a screw threaded jointbetween the members at their smaller ends, said core members having openings leading from their larger to their smaller ends, and means at their smaller ends to allow access of atmosphere to the core abutments.

4:. A core comprising a pair of tapered members adapted to abut at their smaller ends, means whereby the core members may be separated endwise, and means for admitting atmosphere to the core abutments.

In witness that I claim the foregoing I have hereunto subscribed my name this 12th day of January 1923.

EMIL F. CYKLER. 

